Intra-modal retrieval [1]}, [2]} has been intensively investigated in the contexts of keyword-based web document retrieval [3]} and content-based image retrieval  [4]}.
On the other hand, cross-modal retrieval[5]}, [6]}, [7]}, [8]}, [9]}, [10]} emerges as a prospective route for efficiently indexing and searching vast amounts of data with multiple modalities, and is extensively utilized in search engines [11]}, [12]} and E-commerce [13]}, [14]}, to mention a few.
However, these techniques [15]}, [16]}, [14]}, [18]}, [19]} are often limited to unimodal inputs, making them inapplicable to a large number of real-world circumstances non which both the queries and targets include multi-modal information.
